This study focused on understanding the confined crystallization of poly(ethylene oxide) (PEO) in electrospun nanofibers. The effect of thermal treatment on PEO crystallization was also studied. An electrospinning process with a rotating drum collector enabled stretching and aligning of polymer chains, which resulted in the formation of a planar zigzag conformation. The confined environment in nanofibers facilitated an ordered crystal arrangement, resulting in an increase in the degree of crystallinity with a decrease in the fiber diameter. By contrast, large fibers extended solvent evaporation, which resulted in large crystallite sizes. The confined geometry and mechanical force provided by a rotating collector induced the preferred crystal orientation parallel to the fiber axis. Upon thermal annealing, the stretched PEO chains relaxed, resulting in a change from the metastable zigzag conformation to a stable helical conformation. Thermal treatment monotonically increased the melting temperature, degree of crystallinity, and crystallite size of PEO nanofibers regardless of the fiber diameter but did not influence the orientation of the organized crystals.

这项研究的重点是了解电纺纳米纤维中聚环氧乙烷（PEO）的受限结晶。还研究了热处理对PEO结晶的影响。使用旋转鼓收集器的静电纺丝工艺能够拉伸和排列聚合物链，从而导致形成平面之字形构象。纳米纤维中的密闭环境促进了有序的晶体排列，导致结晶度的增加以及纤维直径的减小。相比之下，大纤维延长了溶剂的蒸发，从而导致了较大的微晶尺寸。由旋转收集器提供的有限的几何形状和机械力引起平行于纤维轴的首选晶体取向。热退火后，拉伸的PEO链松弛，导致从亚稳的锯齿形构象变为稳定的螺旋形构象。热处理单调增加了PEO纳米纤维的熔融温度，结晶度和微晶尺寸，无论其纤维直径如何，但均不影响有组织晶体的取向。